Monoazo dye and process of making same.



UNITED STATES Patented November 3, 1903.

PATENT OFFICE.

RICHARD GLEY AND OTTO SIEBERT, OF BERLIN, GERMANY, ASSIGNORS TO AOTIENGESELLSOHAFT FUR ANILIN FABRIKATION, OF BERLIN, GER- MANY.

MONOAZO DYE AND PROCESS OF MAKING'SAME.

SPECIFICATION forming part of Letters Patent No. 743,071, dated November1903- Applioation filed March 26, 1903.

7 T on whom it may concern:

Be it known that we, RICHARD GLEY and OTTO SIEBERT, of Berlin, in theKingdom of Prussia, German Empire, have invented new and usefulImprovements in the Production of Monoazo Dye and Process of MakingSame; and we do hereby declare that the following is a full, clear, andexact description of the invention, which will enable others skilled inIO the art to which it appertains to make and use the same.

Our invention relates to the manufacture of an azo dyestufi which isobtained by combining the diazo compound of the following sulfo-acid:

in which X represents N0 01, or 0H,, with 2 5 beta-oxynaphthoic acid.The coloring-matters thus obtained are most suitable for the preparationof red lakes which are distinguished by their brilliant color and theirfastness against the action of water, oil, and light.

These lakes therefore are extremely fit for use as printing-lakes inlithography and for similar purposes.

The new azo dyes even in the form of their alkali salts are onlyslightly soluble in water and may easily be converted into completelyinsoluble compounds by preparing other metal salts of them. Our new dyesare soluble in concentrated sulfuric acid with a violetred color.

The manufacture of our dyestufi is illustrated by the following example:Dissolve 18.7 parts of para-toluidin sulfo-acid with 11.4 parts ofcaustic-soda lye containing thirtyfive per cent. NaOI-I in water and adda solution of 6.9 parts. of sodium nitrite. Run

Serial No. 149,736. (Specimens) this solution into 4.5 parts ofhydrochloric acid (containing thirty-two per cent. H01) mixed with ice.After stirring for some time the formation of the diazo compound iscompleted. Then pour the diazo compound into a solution of 18.8 parts ofbeta-oxynaphthoic acid and 36.5 parts of soda in water. The combinationtakes place almost immediately. Hereafter heat the mixture to about 80,add some common salt, and filter. It is advantageous to use the dyestuffin the form of a paste. The dried dyestufi is a red powder with ametallic luster.

In the preceding example the para-toluidin sulfo-acid may be substitutedby para-nitranilin sulfo-aoid or by para-chloranilin sulfo-acid withoutessentially changing the result.

Having now described our invention and in what manner the same is to beperformed, what we claim is-- r 1. The herein-described process ofproducing a red azo dye by combining the diazo compound of the followingsulfo-acid:

in which X represents NO ,Ol or CH with beta-oxynaphthoic acid,substantially as described.

2. As a new product the azo dyestufi obtained by combining theparasubstituted diazobenzene-ortho-snlfonic acidwith beta beta-oxynaphthoic acid, being when dried a red powder, slightlysoluble inwater and soluble with a violet-red color in concentrated sulfuric acidand capable of forming brilliant red lakes, distinguished by theirfastness, substantially as set forth.

In Witness whereof we have hereunto signed our names, this 10th day ofMarch, 1903, in the presence of two subscribing witnesses.

RICHARD GLEY. OTTO SIEBERT.

Witnesses WOLDEMAR HAUPT, HENRY HASPER.

